The present invention relates to an electrical connector provided with a means to prevent terminal fittings from rubbing against each other and becoming abraded.
A conventional connector is configured so as to be provided with a pair of male and female connector housings, each having terminal fittings attached thereto, one of these connector housings having a locking arm capable of being resiliently inclined, this locking arm having a stopped member. When the two connector housings are to be fitted together, the locking arm is inclined; the male and female terminal fittings then reach a correct fitted state and make contact, the locking arm returns to its original position. And the stopped member thereof engages with a stopping member of the corresponding housing. The two connector housings are thereby maintained in a fitted state.
In the case described above, the locking mechanism is provided with the inclinable locking arm which, in order to be inclined above or below the corresponding stopping member, needs a specified clearance between the stopped member of the locking arm and the corresponding stopping member. If this clearance is provided, there is the problem that the two housings rattle against each other if they are installed in a location prone to vibration from the exterior, contacting members of the male and female terminal fittings repeatedly rub against one another, and this causes damage such as contacting members gradually being abraded and their contacting force decreasing.
A means to prevent rattling between the male and female housings, so as to prevent the terminal fittings from rubbing against each other and becoming abraded, has been set forth by the present applicant in Japanese Utility Model Registration Number 2542630.
As shown in FIG. 7 of this application, a sealing ring 5 is attached between a terminal housing 2 of a female housing 1 and a hood member 4 of a male housing 3. A flange 5A is provided on a posterior outer circumference of the sealing ring 5, this flange 5A fitting between an anterior edge of the hood member 4 and a protruding wall 6 of the female housing 1, this protruding wall 6 being opposite the anterior edge of the hood member 4. When the fitting of the two housings 1 and 3 is almost completed, the flange 5A of the sealing ring 5 is squeezed resiliently between the hood member 4 and the protruding wall 6. The returning force of the flange SA causes the two housings 1 and 3 to move in a direction of separation, and a stopped member 7A of a locking arm 7 fits tightly with a stopping member 8, thereby preventing the male and female housings 1 and 3 from vibrating against each other.
However, in the above proposal, the flange 5A of the sealing is simply squeezed between the hood member 4 and the protruding wall 6. Consequently, when the flange 5A receives a pushing force, the outer edge thereof moves outwards, and since the pushing force onto the terminal housing 2 is weakened at a posterior edge of the sealing ring 5, the amount of resilient strength which is exercised may be insufficient, and the seal may be damaged.
Further, there is the danger of permanent set-in fatigue in the flange 5A if it is overly compressed. Consequently, a means to prevent this problem is required. In the above proposal, a protrusion 9 protrudes from the protruding wall 6, this protrusion 9 approaching a cut-away member 9A formed in the flange 5A. The anterior edge of the hood member 4 makes contact with the protrusion 9 and prevents further movement in the anterior direction, thereby preventing the flange 5A from being overly compressed. However, this configuration has the problem of being somewhat complex, and an improved solution is required.
The present invention aims to provide the required improvement.
According to the invention there is provided an electrical connector comprising a pair of connector housings adapted for mutual fitting together in a fitting direction, one of said housings having a resilient locking arm adapted to engage the other of said housings to maintain said housings in a fitted state, and a resilient sealing ring being provided between respective circumferential faces of said housings, charactertised in that said sealing ring has a continuous radially outwardly extending flange adapted to be gripped between opposed faces of said connector housings in the fitted condition, one of the sealing ring and connector housings having a pushing surface at an angle to said fitting direction and adapted to urge the outer edge of said flange radially inwardly.
Preferably the pushing surface is provided on the sealing ring and faces said other housing. The pushing surface may be flat or acruate. The pushing surface may alternatively be provided on one or other of said connector housings.
The sealing ring preferably has a tubular portion insertable in a corresponding aperture of one of said housings. The tubular portion may have outer peripheral sealing lips, and internal grooves to improve sealing thereof in said aperture.